From 16dae48e9cd0421106517fc657c8743a14468945 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Sat, 9 Jan 2021 10:48:20 +0100 Subject: [PATCH] vregs: Fix up instantiate_virtual_regs_in_insn for asm goto with outputs [PR98603] If an asm insn fails constraint checking during vregs, it is just deleted. We don't delete asm goto though because of the edges to the labels, so instantiate_virtual_regs_in_insn would just remove the inputs and their constraints, the pattern etc. This worked fine when asm goto couldn't have output operands, but causes ICEs later on when it has more than one output (and furthermore doesn't really remove the problematic outputs). The problem is that for multiple outputs we have a PARALLEL with multiple ASM_OPERANDS, but those must use the same ASM_OPERANDS_INPUT_VEC etc., but the code was adjusting just one. The following patch turns invalid asm goto into a bare asm goto ("" : : : : lab, lab2, lab3); i.e. no inputs/outputs/clobbers, just the labels. 2021-01-09 Jakub Jelinek PR rtl-optimization/98603 * function.c (instantiate_virtual_regs_in_insn): For asm goto with impossible constraints, drop all SETs, CLOBBERs, drop PARALLEL if any, set ASM_OPERANDS mode to VOIDmode and change ASM_OPERANDS_OUTPUT_CONSTRAINT and ASM_OPERANDS_OUTPUT_IDX. * gcc.target/i386/pr98603.c: New test. * gcc.target/aarch64/pr98603.c: New test. --- gcc/function.c | 8 ++++++-- gcc/testsuite/gcc.target/aarch64/pr98603.c | 11 +++++++++++ gcc/testsuite/gcc.target/i386/pr98603.c | 11 +++++++++++ 3 files changed, 28 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/gcc.target/aarch64/pr98603.c create mode 100644 gcc/testsuite/gcc.target/i386/pr98603.c diff --git a/gcc/function.c b/gcc/function.c index 4b9c0a5aa19..a3ed3987b95 100644 --- a/gcc/function.c +++ b/gcc/function.c @@ -1785,12 +1785,16 @@ instantiate_virtual_regs_in_insn (rtx_insn *insn) { error_for_asm (insn, "impossible constraint in %"); /* For asm goto, instead of fixing up all the edges - just clear the template and clear input operands - (asm goto doesn't have any output operands). */ + just clear the template and clear input and output operands + and strip away clobbers. */ if (JUMP_P (insn)) { rtx asm_op = extract_asm_operands (PATTERN (insn)); + PATTERN (insn) = asm_op; + PUT_MODE (asm_op, VOIDmode); ASM_OPERANDS_TEMPLATE (asm_op) = ggc_strdup (""); + ASM_OPERANDS_OUTPUT_CONSTRAINT (asm_op) = ""; + ASM_OPERANDS_OUTPUT_IDX (asm_op) = 0; ASM_OPERANDS_INPUT_VEC (asm_op) = rtvec_alloc (0); ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op) = rtvec_alloc (0); } diff --git a/gcc/testsuite/gcc.target/aarch64/pr98603.c b/gcc/testsuite/gcc.target/aarch64/pr98603.c new file mode 100644 index 00000000000..f75d8e4e23a --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/pr98603.c @@ -0,0 +1,11 @@ +/* PR rtl-optimization/98603 */ +/* { dg-do compile } */ +/* { dg-options "-O0" } */ + +int +foo (void) +{ + int b, c; + asm goto ("" : "=R" (b), "=r" (c) : : : lab); /* { dg-error "impossible constraint in 'asm'" } */ +lab:; +} diff --git a/gcc/testsuite/gcc.target/i386/pr98603.c b/gcc/testsuite/gcc.target/i386/pr98603.c new file mode 100644 index 00000000000..9bf924ec06b --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr98603.c @@ -0,0 +1,11 @@ +/* PR rtl-optimization/98603 */ +/* { dg-do compile } */ +/* { dg-options "-O0 -w" } */ + +int +foo (void) +{ + int b, c; + asm goto ("" : "=r" (b), "=r" (c) : "I" (128) : : lab); /* { dg-error "impossible constraint in 'asm'" } */ +lab:; +} -- 2.30.2